DE102008007940B4 - Safety device for an electrically controlled parking brake and method for operating a safety device for an electrically controlled parking brake - Google Patents

Abstract

Safety device (10) for an electrically controlled parking brake (12) of a vehicle (14) with
A control unit (22) for controlling the safety device (10),
- wherein the control unit (22) is adapted to detect a rolling off of the vehicle (14) when the vehicle (14) is parked,
characterized,
- That a plurality of sensors (16, 18) for directly detecting a movement of a drive element (20) in a drive train (32) are provided by a determination of an orientation in the drive element,
- That the control unit (22) is adapted to detect a rolling away of the vehicle (14) with the ignition (30) off,
- That not all sensors (16, 18) at the same time a certain arbitrary orientation in the drive element (20) by a signal in comparison with the other sensors (18; 16) energiereiches signal and
- That the control unit (22) is adapted to deactivate sensors (16, 18), the in the activation of the safety device (10) present orientation in the drive element ...

Description

The invention relates to a safety device for an electrically controlled parking brake of a vehicle having a control device for controlling the safety device, wherein the control device is adapted to detect a rolling away of the vehicle in a parked vehicle.

The invention further relates to a method for operating a safety device for an electrically controlled parking brake of a vehicle with a control device for controlling the safety device, wherein the control device is adapted to detect a rolling away of the vehicle in a parked vehicle.

Such a security device or such a method is known from DE 10 2004 006 697 A1 known.

Vehicles, such as road or rail vehicles, usually have a parking brake, which can be electrically controlled and is suitable to secure the vehicle in the parked state against rolling. Such parking brake systems are mechanically robust designed for safety reasons, as in the event of a defect uncontrolled rolling of the vehicle could easily lead to incalculable damage.

The disadvantage here is in particular that after inserting the electrically controlled parking brake no control option is provided, which monitors the functioning of the electrically controlled parking brake of the parked vehicle. Also, no possibility is provided to stop a vehicle rolling away because of a defective parking brake.

From the EP 1 445 162 A1 a method for operating a decentralized electro-mechanical brake system is known, wherein in the presence of an insufficient clamping force so far no application force to ensure the vehicle standstill contributing brake device of the brake system provides the missing clamping force.

From the DE 101 57 449 B4 Furthermore, a vehicle braking system is known, in which the forces acting on the braking surfaces are adjusted as a function of a temperature of the braking surface.

The invention has for its object to provide a safety device that monitors the functioning of an electrically controlled parking brake of a parked vehicle.

This object is solved by the features of the independent claims.

Advantageous embodiments and modifications of the invention will become apparent from the dependent claims.

The invention is based on the generic safety device in that a plurality of sensors are provided for directly detecting a movement of a drive element in a drive train by determining an orientation in the drive element.

The control unit is suitable for detecting a rolling away of the vehicle when the ignition is switched off.

Not all sensors simultaneously signal a certain arbitrary orientation in the drive element by a signal that is rich in energy compared to the other sensors. By cleverly arranging sensors in the drive element, it can be ensured that at least one sensor always indicates the orientation of the drive element by means of a signal which consumes little energy compared to the signals of the other sensors, that is to say with low energy.

The control unit is suitable for deactivating sensors which signal the orientation present in the drive element during the activation of the safety device by means of a signal which is high-energy in comparison with the other sensors. Since one sensor is sufficient to detect movement of the drive element, the remaining sensors may be deactivated to reduce the power consumption of the safety device. In particular, those sensors are deactivated which signal the instantaneous position of the drive element by a signal which is more energy-rich compared to the signals of the other sensors.

The switching off of the ignition serves as an additional indicator for stopping the vehicle, which is why the control unit is also suitable for detecting the state of the ignition.

In this context, it can be provided that the control unit is suitable to close a service brake of the vehicle. By closing the service brake a parked with a defective parking brake vehicle can be stopped safely, that is avoided after stopping unintentional rolling of the vehicle.

For this purpose it can be provided that the drive element comprises at least one permanent magnet. A permanent magnet can as wear-free contactors make a movement within the drive element, for example a transmission, of the parked vehicle detectable. In particular, the attachment / integration of the at least one permanent magnet on / in the moving parts of the transmission, that is, the gears or shafts, meant. Alternatively or additionally, existing sensors of an ABS system can also be used, which are arranged in wheel hub areas of the vehicle wheels.

Usefully, it is then provided that at least one sensor is a reed sensor. A reed sensor can detect a movement in the transmission wear-free. The reed sensor is particularly energy-saving because it consumes no quiescent current in the open state.

It can also be provided that at least one sensor is a Hall sensor. A Hall sensor has no moving parts and is therefore not only wear-free, but also very robust.

Furthermore, it can be provided that the control unit is suitable for carrying out a functional check of the at least one sensor while the vehicle is being moved by means of a drive. When the parking brake of the vehicle is opened, the vehicle is usually in motion, which is why this state can be used to check the operability of the at least one sensor. In this way, an essential element of the safety device, namely the sensor can be checked.

Usefully, it can be provided that the safety device can be activated by switching off the ignition. Turning off the ignition of the commercial vehicle is often the last act that the driver performs when parking the vehicle within the cab, which is why a so coupled activation of the safety device makes sense.

It is also conceivable that the safety device can be activated in the absence of the driver by an unsuccessful driver presence control. An unintentional rolling away of the vehicle is conceivable in particular when no driver is present. The checking of the driver's presence and the subsequent activation of the safety device when the driver is absent, therefore, make sense. The absence of drivers can be detected, for example, via sensors in the driver's seat or assumed by closing the driver's cab from the outside. The driver's presence can also be detected via an electric belt tensioning device or monitoring of a belt closure element. Recently, driver detection units are often integrated into existing sensors or control units and have, for example, intelligent infrared sensors, which eliminates the costly additional cabling. Driver seat sensors, which measure and evaluate the weight of the driver, are also usable, for example, for detecting whether a driver is present.

In particular, it can be provided that the control unit is suitable to close the electrically controlled parking brake. If the electrically controlled parking brake is unintentionally opened after the vehicle is parked, for example due to a short circuit or other faulty control, the safety device can correct this error by closing the electrically controlled parking brake again. The closing of the electrically controlled parking brake also includes a retightening of the electrically controlled parking brake to adjust this shrunk at a shrunk brake disc thickness shrunk by cooling and thus prevent rolling away.

In addition, it can be provided that the control unit is suitable to close the drive train of the vehicle. The closing of the drive train of the vehicle, for example by the closing of the clutch, increases the resistance to be overcome by the vehicle, since when rolling away the drive of the vehicle must be moved simultaneously. The engagement of a gear in the transmission can be covered by the closing of the drive train.

In addition, it can be provided that the control unit is suitable for switching a parking pawl arranged in the drive train in order to mechanically block the drive train. A park block pawl blocking the driveline securely prevents insufficient braking of the electrically controlled parking brake.

Furthermore, it can be provided that the control unit is suitable for outputting a warning signal. Such a warning signal may include, for example, an alarm sound output via a signal system of the vehicle, and / or a message transmitted to the driver of the vehicle. The signal system of the vehicle may be, for example, the signal horn or an alarm system integrated in the vehicle. To transmit a message to the driver, the vehicle can report to the driver, for example via a vehicle remote control, for example a door opener, or a mobile device integrated into the vehicle, and notify him of the emergency situation. It is also conceivable, on the mobile device, a parent authority, such as police, fire or traffic, to inform about the emergency situation to To prevent worse, whereby a position indication can be provided via GPS.

Advantageously, it is provided that the safety device can be activated by inserting the electrically controlled parking brake. Since the safety device is to monitor the functionality of the electrically controlled parking brake, activation by inserting the electrically controlled parking brake makes sense.

The invention is based on the generic method in that a plurality of sensors are used for directly detecting a movement of a drive element in a drive train by determining an orientation in the drive element.

A rolling away of the vehicle is detected when the ignition is switched off.

Upon activation of the safety device, sensors are deactivated which signal the orientation present in the activation of the safety device in the drive element by a signal that is more energy-rich than the other sensors.

In this way, the advantages and peculiarities of the safety device according to the invention are also implemented in the context of a method.

This also applies to the following particularly preferred embodiments of the method according to the invention.

This is usefully developed by closing a service brake of the vehicle.

Furthermore, it is advantageous that a functional check of the at least one sensor is carried out while the vehicle is being moved by means of a drive.

Furthermore, it is preferred that the safety device is activated when inserting the electrically controlled parking brake.

Usefully, it can also be provided that the safety device is activated after switching off an ignition.

Advantageously, it can be provided that the safety device is activated in the absence of the driver.

It can also be provided that the drive train of the vehicle is closed.

Preferably, it may be provided that in the drive train a parking pawl is inserted, which mechanically blocks the drive train.

In particular, it can be provided that a warning signal is output.

Furthermore, it can be provided that the electrically controlled parking brake is closed.

Furthermore, it can be provided that a signal emitted by the at least one sensor after the vehicle has come to a standstill is interpreted as a rest signal. This signal may, for example, be a measuring current measured by the sensor.

It can be provided in particular that a change in the rest signal is interpreted as unintentional movement of the vehicle.

Based on this, it can be provided that the modified idle signal is used as a wake-up signal for the control unit.

The invention will now be described by way of example with reference to the accompanying drawings by way of particularly preferred embodiments.

Show it:

1 a schematic representation of a vehicle with a safety device according to the invention;

2 a detailed view of a security device according to the invention and

3 a flowchart illustrating individual process steps.

In the following drawings, like reference characters designate like or similar parts.

1 shows a schematic representation of a vehicle with a safety device according to the invention. The vehicle shown 14 is powered by a drive 28 , which may be an internal combustion engine, for example, via a clutch 34 and a drive element 20 For example, a gearbox that is in a driveline 32 are arranged, driven. It will be the drive 28 Work done on the powertrain 32 on vehicle wheels 44 transferred to a propulsion of the vehicle 14 to enable. The drive element 20 and the clutch 34 are doing over lines 40 with a transmission control 46 Coupled to the clutch 34 opens or closes and the drive element 20 can switch. Furthermore is a service brake 24 in the vehicle 14 arranged over lines 40 with at the vehicle wheels 44 arranged brake cylinders 36 or spring brake cylinders 38 is coupled. The service brake 24 is thus suitable for a forward or backward movement of the vehicle 14 by closing the brake cylinder 36 and the spring brake cylinder 38 to delay or terminate. In addition to the service brake 24 is in the vehicle 14 also an electrically controlled parking brake 12 arranged, which likewise over a line 40 with the spring brake cylinders 38 is coupled. The from the service brake 24 and the electrically controlled parking brake 12 to the spring brake cylinders 38 leading line 40 usually has for the two brake systems 24 . 12 separate brake media guides to control the spring brake cylinders in case of failure of one of the media guides 38 to be able to guarantee. The electrically controlled parking brake 12 is suitable, a parked vehicle 14 by venting the spring brake cylinder 38 to prevent it from rolling away. When bleeding the spring brake cylinder 38 These are closed by biased springs to rotate the associated vehicle wheels 44 to prevent. The transmission control 46 , the service brake 24 and the electrically controlled parking brake 12 are via electrical lines 42 with a control unit 22 a security device 10 coupled. The security device 10 also includes sensors 16 . 18 that are capable of movement in the drive element 20 to detect. This is related to 2 explained in more detail.

After parking the vehicle 14 and inserting the electrically controlled parking brake 12 should the vehicle 14 be secured against unintentional rolling away. This vehicle condition may be from the safety device 10 be monitored. If the vehicle 14 Rolls up, over the vehicle wheels 34 and the drive train 32 the components of the drive element 20 , in particular in the drive element 20 arranged gears and shafts, moves. This movement is via the sensors 16 . 18 directly detectable and is sent to the control unit 22 forwarded. In this case, direct means, in particular, without the interposition of gearbox-free components of the drive train 32 , The control unit 22 is now able to take appropriate countermeasures against rolling away the vehicle 14 initiate. For example, the controller 22 the service brake 24 to close the brake cylinder 36 and / or the spring brake cylinder 38 cause. It is also possible that the control unit 22 the transmission control 46 causes the clutch 34 close to the internal resistance of the drive 28 for braking the vehicle 14 to use. The control unit 22 However, the electrically controlled parking brake can also be used 12 cause the spring brake cylinders 38 close again. This can be useful in particular when the spring brake cylinder 38 only mistakenly, for example by a short circuit in electronics, were opened. Also in this way is a retightening of the electrically controlled parking brake 12 possible, if by contracting the brake disc when cooling the electrically controlled parking brake 12 is not stretched enough. The control unit 22 can also give a warning signal. This can be an acoustic signal via a signal system of the vehicle 14 be, for example, a horn or an alarm system. The transmission of a warning message to the driver of the vehicle 14 is also possible. This may be the controller 22 for example, a return channel of a remote control, for example a door opener, or one in the vehicle 14 operate integrated mobile device. The latter is also suitable for informing a higher-level authority, for example the police, the fire brigade or the traffic guard about the emergency situation, wherein a position of the vehicle determined by a GPS system 14 is added to the warning message.

2 shows a detailed view of a security device according to the invention. The security device 10 includes next to the controller 22 and in a sensor array 52 arranged sensors 16 . 18 a detector circuit 50 with an edge detector 62 that from the sensors 16 . 18 processed signals processed. The sensor arrangement 52 is in close proximity to a transmission part 60 , For example, arranged a rotatably arranged in the gear gear and can by means of the sensors 16 . 18 the movement of the transmission part 60 on the basis of on the transmission part 60 arranged permanent magnets 26 detect. The sensor arrangement 52 Optionally, it can also detect the movement of several moving parts simultaneously when the sensors 16 . 18 are arranged accordingly. For example, a kitas sensor from VDO can be used as the sensor. The permanent magnets 26 For example, they can be integrated into the teeth of a gear. If the vehicle 14 is in motion, then the sensor arrangement 52 over an ignition 30 powered, and can be a signal 56 generate, by means of which the control unit 22 the functionality of the sensors 16 . 18 can check. Are not all sensors 16 . 18 intact, the controller can 22 to issue an appropriate error message. Holds the vehicle 14 on, so remains the transmission part 60 in a fixed but apriori arbitrary position. With a suitable arrangement of the permanent magnets 26 and the sensors 16 . 18 It is possible that in every possible position of the transmission part 60 at least one sensor 16 ; 18 is open while the other sensors 18 ; 16 are closed. The term open or closed refers to a measurement signal generated by the sensor, in particular a measurement current, wherein closed designates the presence of a relevant measurement current and open the absence of a relevant measurement current. The closed sensors 18 ; 16 So generate a high-energy signal to the current position of the transmission part 60 while the sensors are open 16 ; 18 output a low energy signal to the same position of the transmission part 60 display. Those sensors 16 . 18 After stopping the vehicle 14 and the engagement of the electric parking brake 12 can be closed by the control unit 22 be deactivated for energy saving. Will the vehicle 14 turned off, that means in particular the ignition 30 turned off, so will the safety device 10 put into a standby mode and via a connection permanent plus 48 energized. At least one of the open sensors 16 ; 18 remains activated and can cause movement of the gear unit 60 or the permanent magnet 26 to capture. If such a movement so closes the hitherto opened sensor 16 ; 18 and generates a corresponding signal, for example a non-zero measuring current. This measuring current is provided by the detector circuit 50 conditioned, that is in particular debounced by a Schmitt trigger, amplified and as a signal 54 to the control unit 22 forwarded to wake it up from standby mode. The detector circuit 50 is only available for a parked vehicle 14 and only with a change, that is, the detection of an edge, a current or current pulse for starting the controller 22 from. Ideal is a hard-wired high-impedance edge mirror circuit with different time windows, which detects the change by the time offset. The control unit 22 can now in turn signals 58 to the electrically controlled parking brake 12 , the service brake 24 and the transmission control 46 send to the vehicle 14 to stop again. These signals can, for example, first wake up the corresponding systems 12 . 24 . 46 then take concrete steps to brake the vehicle 14 to effect. It is also conceivable that the systems 14 . 24 46 receive only a wake-up signal and then independently check the vehicle condition and / or the vehicle 14 stop again. The output of a warning signal, as in 1 described is also possible.

3 shows a flowchart for illustrating individual process steps. It starts at step 100 in which the parking brake is closed. After closing the parking brake is in step 102 the time interval .DELTA.t waited to ensure that the vehicle, in particular the transmission has come to a standstill. Will now be in step 104 the ignition is switched off, so is at step 106 the safety device is activated and thus the monitoring is started. It is also conceivable to additionally or alternatively couple the monitoring to a driver presence check or door lock control. The monitoring is started when the driver is no longer in the driver's cab. The safety device now monitors the measurement signals generated by the sensors and, if the measurement signals change, 108 -Yes at 110 appropriate countermeasures. The countermeasures were already related to the 1 and 2 described. If no change is detected, 108 -No, will join 106 continued with the monitoring. It should be noted that the monitoring can also be terminated by the intended release of the parking brake. The change, for example, trigger a current pulse or even be a current pulse, the current pulse then wakes up the control device of the safety device, which in turn initiates by a wake-up pulse to other systems countermeasures. If the other systems independently check the vehicle condition and initiate countermeasures according to their possibilities, the control unit could also be integrated into the detector circuit.

The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be essential to the realization of the invention both individually and in any combination.

LIST OF REFERENCE NUMBERS

10

safety device

12

electrically controlled parking brake

14

vehicle

16

sensor

18

sensor

20

driving element

22

control unit

24

service brake

26

permanent magnet

28

drive

30

ignition

32

drive train

34

clutch

36

brake cylinder

38

Spring brake cylinder

40

management

42

electrical line

44

vehicle

46

transmission control

48

continuous positive

50

detector circuit

52

sensor arrangement

54

signal

56

signal

58

signal

60

transmission part

62

edge detector

100

Close the parking brake

102

Wait time interval Δt

104

Ignition switched off

106

Monitoring the parking brake

108

Change of the silence signal?

110

Take countermeasures

Claims (26)

Safety device ( 10 ) for an electrically controlled parking brake ( 12 ) of a vehicle ( 14 ) with - a control unit ( 22 ) for controlling the security device ( 10 ), - whereby the control unit ( 22 ) is suitable for a parked vehicle ( 14 ) a rolling away of the vehicle ( 14 ), characterized in that - several sensors ( 16 . 18 ) for directly detecting a movement of a drive element ( 20 ) in a drive train ( 32 ) are provided by a determination of an orientation in the drive element, - that the control unit ( 22 ) is suitable, a rolling of the vehicle ( 14 ) with the ignition switched off ( 30 ) - that not all sensors ( 16 . 18 ) at the same time a certain arbitrary orientation in the drive element ( 20 ) by one compared to the other sensors ( 18 ; 16 ) signal high-energy signal and - that the control unit ( 22 ), sensors ( 16 . 18 ) that deactivate the activation of the security device ( 10 ) present orientation in the drive element ( 20 ) by one compared to the other sensors ( 18 ; 16 ) signal high-energy signal. Safety device ( 10 ) according to claim 1, characterized in that the control unit ( 22 ) is suitable, a service brake ( 24 ) of the vehicle ( 14 ) close. Safety device ( 10 ) according to claim 1 or 2, characterized in that the drive element ( 20 ) at least one permanent magnet ( 26 ). Safety device ( 10 ) according to one of the preceding claims, characterized in that at least one sensor ( 16 . 18 ) is a reed sensor. Safety device ( 10 ) according to one of the preceding claims, characterized in that at least one sensor ( 16 . 18 ) is a Hall sensor. Safety device ( 10 ) according to one of the preceding claims, characterized in that the control unit ( 22 ) is suitable, a functional check of the at least one sensor ( 16 . 18 ) while the vehicle ( 14 ) using a drive ( 28 ) is moved. Safety device ( 10 ) according to one of the preceding claims, characterized in that the safety device ( 10 ) by switching off the ignition ( 30 ) is activated. Safety device ( 10 ) according to one of the preceding claims, characterized in that the safety device ( 10 ) is activated in the absence of the driver by an unsuccessful driver presence control. Safety device ( 10 ) according to one of the preceding claims, characterized in that the control unit ( 22 ), the electrically controlled parking brake ( 12 ) close. Safety device ( 10 ) according to one of the preceding claims, characterized in that the control unit ( 22 ) is suitable, the drive train ( 32 ) of the vehicle ( 14 ) close. Safety device ( 10 ) according to one of the preceding claims, characterized in that the control unit ( 22 ), one in the drive train ( 32 ) arranged park pawl to the driveline ( 32 ) to block mechanically. Safety device ( 10 ) according to one of the preceding claims, characterized in that the control unit ( 22 ) is capable of outputting a warning signal. Safety device ( 10 ) according to one of the preceding claims, characterized in that the safety device ( 10 ) by inserting the electrically controlled parking brake ( 12 ) is activated. Method for operating a security device ( 10 ) for an electrically controlled parking brake ( 12 ) of a vehicle ( 14 ) with - a control unit ( 22 ) for controlling the security device ( 10 ), - where in a parked vehicle ( 14 ) a rolling away of the vehicle ( 14 ), characterized in that - a plurality of sensors ( 16 . 18 ) for directly detecting a movement of a drive element ( 20 ) in a drive train ( 32 ) by a provision of a Orientation can be used in the drive element, - that rolling of the vehicle ( 14 ) is detected when the ignition is switched off, and - that upon activation of the safety device ( 10 ) Sensors ( 16 ; 18 ), which are disabled when activating the security device ( 10 ) present orientation in the drive element ( 20 ) by one compared to the other sensors ( 18 ; 16 ) Signal more energetic signal. A method according to claim 14, characterized in that a service brake ( 24 ) of the vehicle ( 14 ) is closed. Method according to claim 14 or 15, characterized in that a functional check of the at least one sensor ( 16 . 18 ) while the vehicle ( 14 ) using a drive ( 28 ) is moved. Method according to one of claims 14 to 16, characterized in that the safety device ( 10 ) when inserting the electrically controlled parking brake ( 12 ) is activated. Method according to one of claims 14 to 17, characterized in that the safety device ( 10 ) after switching off an ignition ( 30 ) is activated. Method according to one of claims 14 to 18, characterized in that the safety device ( 10 ) is activated in the absence of the driver. Method according to one of claims 14 to 19, characterized in that the drive train ( 32 ) of the vehicle ( 14 ) is closed. Method according to one of claims 14 to 20, characterized in that in the drive train ( 32 ) a parking pawl is inserted, the drive train ( 32 ) mechanically blocked. Method according to one of claims 14 to 21, characterized in that a warning signal is output. Method according to one of claims 14 to 22, characterized in that the electrically controlled parking brake ( 12 ) is closed. Method according to one of claims 14 to 23, characterized in that after standstill of the vehicle ( 14 ) of the at least one sensor ( 16 . 18 ) emitted signal is interpreted as a quiet signal. A method according to claim 24, characterized in that a change of the rest signal as unintentional movement of the vehicle ( 14 ) is interpreted. A method according to claim 25, characterized in that the changed idle signal as a wake-up signal for the control unit ( 22 ) is used.

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